A practice now common in the telephone industry is to provide a subscriber, typically a business or commercial entity, with a single telephone number to serve diverse geographical areas or territories. Calls placed to that number are routed to respondents who are appointed to serve the respective areas from which the calls originate. While the terminology may differ, depending on the exact context, the single telephone number is sometimes referred to as a "virtual" number since it represents no telephone station in particular, but rather is the calling number for a plurality of stations, each of which may have its own actual directory number.
Virtual numbers have been used in a long-distance context whereby a single number is promoted on a large scale, typically nation-wide, and calls to the number are carried by an inter-exchange, or long distance carrier. The number for these wide area services is usually a special service access number such as an 800 or 900 number, depending on whether the called party or the caller is to be responsible for the call charges. The prior art is predominantly directed to handling calls received on a wide area basis and from areas whose boundaries are rather static and predefined.
A patent to Weber, U.S. Pat. No. 4,191,860, for example, discloses a system whereby a caller dials an 800 number, which, along with the caller's area code (i.e., the NPA, or numbering plan area code), is then used to access a translation table stored in a database system and retrieve an ordinary telephone number to which the call is consequently routed. This is the so-called WATS to POTS translation (Wide Area Telephone Service to Plain Old Telephone Service), now widely deployed by interexchange carriers in a variety of forms. Since the NPA is indicative of a certain geographical area from which the call originates, the translation can be made to yield a POTS number for a party who is especially suited to respond to calls that originate from that area. Thus, callers from different areas, as determined from their area codes, may be routed differently. This arrangement is adequate only if all calls from the same area code are to be routed to the same destination.
Another patent, U.S. Pat. No. 4,757,267, to Riskin, discloses a system that directs an 800 call, with dialed digits that uniquely identify a product or service, to a dealer in those goods or services who is located in some proximity to the calling station. From knowledge of the originating telephone number the call is first routed to a service company in the general vicinity of the caller. Once the nearest dealer is determined, that dealer's telephone number is dialed automatically.
Riskin suggests use of a database according to the Weber model whereby that database, upon being queried with the 800 number and the NPA, sets up a call to another database, providing to it the dialed 800 number and the calling station's NPA and exchange code. The second database system determines the nearest dealer and the POTS number is returned through the facilities associated with the first database for call completion. The focus of the Riskin patent is on getting the long distance caller to the dealer who happens to be closest even though that dealer may not be the dealer assigned to a predefined territory.
A patent to Wegrzynowicz, U.S. Pat. No. 5,136,636, also routes calls to local dealers by building upon the use of a Weber type of database. In operation, a caller dials the virtual 800 number, and .a primary database is accessed using the NPA of the caller and the 800 number; the output of the primary database is a number that identifies one of a plurality of secondary databases for a customer, and a key identifying the customer, for access. That information is then returned from the database, through the associated signaling system, to a network screening office. A translation is made to determine which secondary database of the customer to access. The access key plus the first six digits of the caller's directory number or the entire number is then cross-referenced to a local dealer telephone number, which is returned to the switching system of the network for call routing. The patent expressly recognizes that, only under special circumstances are these techniques applicable for intra-LATA or local services.
U.S. Pat. No. 5,311,572 to Friedes et al., describes a system for processing a database-queried call and uses the call processing capabilities of a carrier's database and a subscriber's database as part of the total communication switching system. The carrier's database is a routing database. The subscriber's database contains calling party identification information including background of the caller. Origination information is forwarded by the originating switch to the carrier's database, which sends it to the subscriber's database. The subscriber's data base uses prestored programs and caller's related information to formulate a processing label for the call. The processing label is comprised of a routing label to select a destination number for the call and an end point label which includes information to be passed to the subscriber's premise equipment. A billing information label is also provided.
U.S. Pat. No. 4,313,035 to Jordan et al., describes the use of an intelligent network to provide a person locator service through multiple exchanges of the switched telephone network. The system provides subscriber access to the subscriber's data in the central data base of the intelligent network, to input data for controlling the person locator service. Each subscriber to the locator service has a unique person locator telephone number. To access the system to update data in the data base, the subscriber dials 0700 and his unique person locator telephone number. The telephone switching office routes the call to a traffic service position system (TSPS), which prompts the caller to receive further digits from the subscriber. The subscriber inputs a three digit access code, indicating the type of update call, and a four digit personal identification number. If calling from the remote station to which the subscriber wishes his calls routed, the local switching office forwards the line identification number of that station to the TSPS. The TSPS forwards the dialed information and the line identification to the data base for updating the particular subscriber's location record.
An absent subscriber can input a number to which calls are to be completed, such as the number where the subscriber can be reached, into the central data base. A caller wishing to reach the subscriber dials the subscriber's unique person locator number. A telephone switching office having access to CCIS sends the dialed number to the central data base. The data base retrieves the stored completion number for the called subscriber and forwards that number back to the switching office to complete the call.
Copending application Ser. No. 08/388,058 (680-101), identified earlier and hereby incorporated by reference, recognizes the need for techniques to facilitate somewhat more localized virtual number usage and that are particularly adaptable to prescribe call routing from territories whose boundaries are subject to change from time to time. Such needs are expressed by example of a local business having several geographically separated branches that serve call-in customers. A call directed to a single virtual number is routed to an appropriate branch on the basis of geographical location of the calling party, through use of the AIN network and the public switched telephone network. The AIN system is described in detail in U.S. Pat. No. 5,247,571 to Kay and McConnell, the disclosure of which is incorporated herein by reference. Each call to the virtual number initiates access to the ISCP database to obtain information from the associated customer processing record to complete the call to the appropriate destination branch.
In addition to the functionality provided by the systems described in the prior art, as well as that of the copending application, a need exists for providing extended flexibility to subscribers subject to call redirection. The subscriber, for example, may operate from a single location at certain hours while requiring redirection of calls dialed to the directory number of the location to other destinations during off hours. In such event, the dialed number is not a virtual number as it is the actual directory number of the on hours location.
In many instances the subscriber may not be a business entity that has a relatively constant complement of branch locations. The number of stations that are available to receive calls and the identity of such stations are parameters that may be variable over time. The ability more easily to designate and change call redirection destinations and to schedule assignments more quickly than currently available are highly desirable features.
By way of example, a "hotline" service environment would benefit greatly from such flexibility. Such service would provide telephone counseling to patients, for example persons going through addiction withdrawal, at any time regardless of whether a counselor is physically present at a counseling center. A single "hotline" telephone number would be published. In off hours, when the center is not staffed, calls dialed to the published hotline number are connected to an available counselor "on call" and located near the caller.
Counselors may be professionally employed and/or volunteers, such as recovered addicts. Redirected calls in most cases would be connected to counselors' residences. It would be important to identify whether or not incoming calls are "hotline" calls, considering their sensitive nature. With provision of such identification, parties other than the counselor at the destination location would be aware not to answer. Such identification would only be necessary during "on call" periods. While telephone companies provide a service known under a variety of names such as "IdentaRing.sup.SM " to provide a different ringing signal to a line depending on which of a plurality of line assigned directory numbers is dialed, such service would not sufficiently meet the needs of a "hotline" counselor.
The currently available distinctive ringing services are more fully described in copending application, Ser. No. 07/936,455, filed Aug. 28, 1992. In summary, multiple directory numbers are assigned to a subscriber line. The telephone central office switch connected to that line will applying a distinctive ringing signal to incoming calls for each assigned directory number to produce different audible rings at the subscriber's premises. For a call dialed to the subscriber's main number, the local telephone office switch identifies that number to apply a standard ringing signal (two seconds on, four seconds off) to the called subscriber's line. If a call is dialed to a second assigned number, the local telephone office switch identifies the number and applies a different ringing signal to the line.
The "IdentaRing.sup.SM " type service functionality is set in the central office switch when the service is initiated and the multiple directory numbers are assigned. The service remains constantly in effect until terminated. There is no provision of the multiple distinctive ringing feature to a line that is assigned a single directory number, or for selective application of a distinctive ringing signal only for redirected calls, such as would be useful in the "hotline" environment.
A "hotline" service is likely to include volunteer or nonprofessional counselors as well as professional administrators. With respect to setting workload schedules, administrators are delegated widespread functions, such as authorization of counselors and administrators, activation of any of the authorized individuals for accepting counseling calls, and deauthorization of such individuals. The counselor's scheduling functions are more limited to activation or deactivation of the individual counselor for a counseling call. Current telephone services do not provide automated fulfillment of these functions in response to input by the respective individuals.